— With football season in full swing, can concussions be far behind? Once thought of as nothing more than a benign “bellringer,” neuroscientists now know these blows to the head can cause serious cognitive and physical problems, both in the short and long term.

In their book, "The Concussion Crisis: Anatomy of a Silent Epidemic," health journalist and msnbc.com contributor Linda Carroll and sports writer David Rosner reveal the stories of people whose lives have been irrevocably changed by concussions. But they also offer hope. As the public health message about the seriousness of concussions reaches more people, future generations of athletes will not only be safer, but can look forward to a brighter future -- once the game is over.

Rosner: Back in the dark ages of the 1980s when I started covering sports, concussions were barely on the radar. It wasn’t until recently that there was a realization that concussions and more severe traumatic brain injuries (TBIs) are all on the same spectrum. That’s an important realization and a major change in how concussions are looked at. We felt that this was something all athletes needed to know.

Carroll: I’ve been a health writer for 20 years and I didn’t know anything about the long-term impact of concussions. Then I did a couple of stories about people with TBIs, and I was astounded to discover the people I interviewed seemed just like you and me, until they had to perform some task. That’s when some subtle and not-so-subtle deficits came out. I figured if I didn’t know about this, probably most people didn’t. I wanted to let everyone know how dangerous concussions can be.

Carroll: The injury often doesn’t show up on CAT or MRI scans because the damage from a concussion is to individual cells that can be scattered throughout the brain. The only way a doctor can see a concussion on a scan is if all the damaged cells are next to one another. So, doctors are left to diagnose a concussion based on symptoms like confusion or blurred vision. The treatment is rest, but in some severe cases medications can be used to target specific symptoms like sleep loss or migraines. Some people wind up needing rehab, too.

Carroll: I think things are changing, but it’s a very slow change. One study showed that more than 40 percent of high school athletes were playing again before their brains had time to recover.

Carroll: Only a concussion expert can make that decision. Some schools are using a technology called ImPact (Immediate Post-Concussion Assessment and Cognitive Testing), which was developed at the University of Pittsburgh. Student athletes are given a baseline test at the beginning of a season. If they get a head injury, they are given another test to see how they score. If the new score is below baseline, they sit out. And they stay out until the score returns to normal and all their symptoms have cleared up.

Rosner: Some changes can be made to make each sport safer. But the truth is you can’t prevent all concussions in sports any more than you can prevent them in fender benders. It’s part of the game, whether that’s football, hockey, soccer – or even cheerleading. We hope that the realization that repeated concussions can lead to long lingering symptoms, as well as recent reports linking repeated concussion to dementia, will show the importance of proper concussion management. And that means rest until all symptoms disappear.

Carroll: Not really. The helmet protects your skull, not your brain. One clinician said to us if you could encase the brain in cement, then maybe the brain wouldn’t get hurt when the head was jolted. The brain floats in fluid inside the skull. The best analogy I can think of is this: If you crash your car and don’t have a seat belt on, you’re going to slam into the windshield. Similarly, your brain, which has nothing holding it in place, slams forward when you stop suddenly, like you would if you collided with another player. So, no matter how much you protect the skull, the brain is still going to get hurt.

Rosner: Yes. I was 14 years old when I was lucky enough to attend the first Ali-Frazier fight in Madison Square Garden. It’s still this magical memory. But after analyzing what boxing does to the brain for the book, I now feel this pang of guilt about being a boxing fan.

Carroll: I have a daughter who is 7 and plays soccer. Now, if I’m there and I see my child getting slammed in the head, I'm going to get in the coach’s face and tell him to get my kid out of a game. As she gets older I'm not going to be able to be there for every game and every practice. I'm hoping that with public education I'll be able to trust her coaches and trainers to do the right thing.